[brennannovak]

With enough (and the right kind of) clients a "Centralized" service could be seen as distributor to independent nodes. From there, with the right archiving / sharing features of those "clients" those independent nodes can start to become a decentralized service. The internet itself relies on centralized DNS standards organization & servers. To me, App.net (and their commitment to users being customers instead of a product) represents a move in this direction.

[joebadmo]

Maybe, but they haven't even really said anything about it. In contrast, check out http://theopenphotoproject.org/ , which has both a centralized system, but it also an open source project that you can self-host. IMHO, much better idea, implementation, and I had a lot less to be vaguely suspicious about. OpenPhoto basically did everything right that App.net is doing wrong.

[bad_user]

OpenPhoto has different constraints though.

When sharing a bunch of photos on OpenPhoto or Flickr or whatever, the social network available to you is not as important as the act of storing that photo somewhere. That's because you can always take that URL and paste it on Facebook or Twitter.

You can then argue that Facebook and Flickr provide value to photo enthusiasts because through them you can see the photos of friends and other people.

But that's not really what OpenPhoto is about and let me quote its description:

     A photo application that lets you store 
     your photos on Dropbox, Amazon S3 or in your garage

Don't get me wrong, I'm actually thinking of using OpenPhoto, but that's only because I want my photos backed-up in the cloud and easily accessible whenever I want, and not much else.